Typically, turbines are driven by a relatively continuous source of pressurized or rapidly moving fluid. For example, hydraulic turbines usually, if not always, are driven by a substantially continuous stream of water which descends through a certain elevation or "head"; a turbine of an aircraft turbojet engine is driven by a substantially continuous stream of air which is pressurized by a continuously rotating compressor and by continuous combustion of a fuel added to the pressurized air.
In both of these devices, incoming fluid is supplied substantially continuously. Aa fluid inlet is provided for the incoming fluid and an outlet, separate from the inlet, is provided for exhausting the fluid after the fluid has supplied energy to the rotating turbine. Thus the fluid is unidirectionally supplied to the turbine through an inlet means and unidirectionally exhausted from the turbine through an outlet means separate from the inlet means.
In my previously mentioned copending application, Ser. No. 408,288, there is disclosed a device wherein rotary or circuitous motion of an object is induced in a chamber in response to fluid flow in the chamber resulting from a source of oscillatory fluid pressure being connected to the chamber via only a single port or passageway which serves both as an inlet and outlet. The apparatus disclosed in Ser. No. 408,288 is a relatively inefficient, thermally driven oscillating free piston apparatus having a minimum number of moving parts; the apparatus develops an oscillatory pressure variation in a rebound chamber and has certain advantages for use, inter alia, as a novelty lamp or as a display or physics demonstration device. The rebound chamber contains an object that undergoes motion having a rotational component that is induced by the oscillatory flow of fluid in the rebound chamber. Generally, the object has an unpredictable path and cannot do useful work.
Rotary turbine compressors, such as mentioned above, are inefficient in small sizes, more so than piston compressors. Also, turbine type energy converters, such as turbo-generators, are noisy unless operated in a closed cycle, which reduces their efficiency, whereas certain piston compressors or piston type energy converters, such as those of the Ericsson or Stirling cycle type, are quiet. However, piston compressors typically require check valves to produce a continuous supply of pressurized fluid for driving a turbine. Check valves can affect the life, as well as the efficiency, of such compressors.
It is known that a lightweight object, such as a table tennis ball, can be supported by a steady stream of air directed upwards in a substantially vertical direction. The air stream exerts a driving and stabilizing force on the ball as a result of fluid pressure. The object remains approximately on the mean flow axis of the stream as a resultt of differential fluid pressure on the ball in accordance with the Bernouli effect, and is positioned in height approximately at a point where the net upward force of the air stream on the object is equal to the gravitational force exerted on the object.